Mosquitoes can live in almost any environment, with the exception of extreme cold weather. They favor forests, marshes, tall grasses and weeds, and ground that is wet at least part of the year. Because they must have water in order to thrive, their habitats break down into two basic types:
Permanent water mosquitoes tend to lay their eggs in clumps, called rafts, of 50 to 300 on the surface of standing water at the edges of lakes and ponds and among the vegetation in swamps and marshes. Some species prefer clean water, while Culex pipiens, the northern house mosquito, prefers stagnant or polluted water.
Culex and Anopheles mosquitoes are among the most common permanent water mosquitoes. These mosquitoes are most active when the average temperature is above 70 degrees. Their eggs must stay in water in order to survive and usually will hatch within a couple of days, releasing larvae to begin the development process.
Many permanent water mosquitoes can also breed in containers that collect and hold water, such as wading pools, buckets or toys left outside.
Floodwater mosquitoes lay their eggs in moist soil. The eggs, as many as one million per acre, will dry out as the ground does, then hatch when rains saturate the ground and water levels begin to rise. Floodwater habitats include:
- Drainage ditches that fill during storms.
- Woodland pools created by melting snow, or spring and early summer rains.
- Floodplains along the banks of streams and rivers.
- Irrigated pastures and fields.
- Meadows and other soft ground where depressions form.
Common species include the Aedes vexans, also known as the inland floodwater mosquito. Mosquitoes that breed in floodwater habitats usually become a problem about seven to 10 days after a heavy rain, and subside in about a week or two.
Floodwater mosquitoes also breed in containers. Aedes albopictus, the Asian tiger mosquito, prefers the insides of old tires where dirty water collects, and Aedes triseriatus prefers treeholes that gather rainwater.